Mixing tank and the like



v 25, 1939. 1 W CORR 2,167,344

MIXING TANK AND THE LIKE Filed March 23, 1938 2 Sheets-Sheet 1 2f/@f4 @12011-1211, efjtn fr??? July 25, 1939. f J. w CQRR 2,167,344

MIXING TANK AND THE LIKE Filed March 23, 1958 2 Sheets-Sheet 2 Patented July 25, 1939 UNITED sTATEs PATIELNT oFFicE MIXING TANK ANDl THE LIKE John William Corr, East Greenwich, R. I.

Application March 23, 1938, Serial No. 197,673

` 5 Claims. (Cl. 257-212) and unless the heat is dissipated as fast as it generates the material boils violently and may The present invention relates to improvements in vessels, vats or tanks for mixing and storing chemicals and more particularly to a tank having a surrounding chamber for circulating a con- 5. ditioning medium to' add or remove heat during the mixing operation or storage of the contents.

One object of the invention is to provide a jacketed mixing or storing tank of the type indilp, cated for transferring heat from the material in the `tank to the conditioning medium in the jacket at a rapid rate 1 i Another object of the invention is to provide a mixing or storage take of lead or other chemical-resistant material which is supported by a perforated inner shell of the jacket to be 'directly contacted by the conditioning medium in the surrounding chamber through the perforations in the shell. V

Still another object of the invention is to provide a mixing or storage tank of the type indicated of simple construction to adapt it for economical manufacture and increased efficiency in performing its intended function.

Further objects of the improvement are set `forth in the following specification which ydescribes a preferred form of construction of the apparatus, -by Way of example, as illustrated by the accompanying drawings. In the drawings: 3 0 Fig. 1 is a side elevational view of a jacketed mixing tank incorporating the novel features of the present invention;

Fig. 2 is an enlarged top plan view of the jacketed tank shown partly in section to illusf 5 trate the interior of the tank and the agitating paddles therein;

Fig. 3 is a transverse sectional view through the jacketed tank showing the spaced relationship of the inner and outer shells of the jacket and 40 the tank or lining supported by the inner shell;

Fig. 4 is an enlarged view of a portion of the jacketed tank shown partly in section to illustrate the perforations in the inner shell of the jacket through which the conditioning medium 45 directly contacts the tank or lining; and

y Fig. 5 is a part-sectional view similar to Fig. 4 showing a Wire mesh basket for supporting the lead tank or lining in spaced relation to the outer shell of the jacket and providing interstices (50 through which the conditioning medium directly contacts the lead tank or lining.

When sulphonating oils, neutralizing acids with ,alkalies, or in other mixing operations and the storage of materials involving similar chemical u reactions, heat is generated at a very rapid rate even explode.

To complete other chemical reactions it is necessary to add heat to the mixture.

lmxing tanks for acids are a lead lining which is inert to the acids.

other chemicals are used usually provided with When other tank or lining material may be necessary. Lead lined mixing tanks With'a Water jacket have been found unsatisfactory for exothermic reactions as the supporting shell for the lead lining renders the Wall quite vthick which, together With the joint between the shell andy lining, reduces the rate of heat transfer to such an extent that the heat cannot be removed as fast as it is generated. Therefore, the general practice has been to provide a coil within the tank for circulating a conditioning medium to remove heat from the mixture at a rapid rate while agitating the mixture around the coil by means of suitable paddles. Such coils when clean are satisfactory to heat `or cool a mixture, but they soon become crusted or caked with a sludge which reduces the rate of heat transfer and impedes the circulation of the mixture in the tank. This caked or crusted 4sludge is difficultI to remove and the coils themselves interfere with the normal cleaning of the tank. The present invention provides a jacketed lmixing tank which is adapted to transfer heat at a rate commensurate with the heat transfer through coils within the tank while eliminating the attendant disadvantages of such coils.

`Referring now to the drawings, the invention is herein shown as embodied in a. jacketed mixing tank 2 of cylindrical fo rm having a generally vmanner from that herein s hoWn.

The jacketed tank 2 comprises an outer shell l0, an inner shell Il and a tuting the tank proper, the

lead lining l2 constiouter and inner shells and lining being of the same contour and adapted to fit one within the other.

may be either in the form The outer shell I0 of a casting or fabricated from sheets of any suitable material such as iron, steel or the like to give it the necessary strength, and preferably it is Yprovided with a laterally-extending annular flange I3 at its upper edge.

'I'he inner shell H is of the same contour as A lil) face.

the outer shell IIJ but of smaller dimensions, being adapted to be held suspended within the outer shell IIJ, by means of a laterally-extending annular flange I4 .at its upper edge which overlies the flange I3 on the outer shell, see Fig. 3. Due to the corresponding configuration of the tWo shells I4 and II the sides and bottom of the inner shell are spaced from the sides and bottom of the outer shell to provide a chamber I5 therebetween for circulation of the 'conditioning medium, such as Water or the like. For this purpose an inlet nipple I6 is Welded or otherwise sealed in an opening adjacent the bottom of the outer shell I5; and an outlet nipple I1 is similarly sealed in an opening adjacent the topl of the shell. The outlet nipple I1 is connected to a suitable drainpipev I8, while the inlet nipple I6 is connected to a T I9 shown in Fig. 1. A branch 20 from the T I3 is suitably connected to a source o-f supply of heating medium, such as hot Water or steam, and a branch 2I from the T is arranged to supply a cooling medium, such as tap Water or a refrigerated brine, if required; `the flow of the conditioning medium in the branches 20 and 2l being controlled by suitable valves 22 and 23. As thus far described the tank is similar to mixing tanks of usual construction.

In accordance with the present invention the inner shell II has perforations 30 over its entire area and is arranged to support the relatively thin lining i2 which constitutes the tank proper. The tank or lining I2 may be composed of lead, or a lead alloy, inert to acids, to adapt it for use in sulphonating oils or for other chemical reactions including acid ingredients; or the lining may be composed of any other suitable material inert to particular chemicals, such materials falling Within the scope of the present invention. In the form of the invention illustrated in Figs. 1 to 4, the inner shell I I may be a casting or fabricated from sheet stock of any suitable material such as iron, steel or the like and having closely related perforations 3!) punched or bored therethrough at regular intervals over its entire Sur- The lead tank or lining I2 is inserted into the perforated shell I I and pressed against its sides and botto-m with a portion 32 at its top folded outwardly and over the edges of the flanges I3 and I4 and then inwardly under the flange I3. Annular plates 33 and 34 are clamped against the top and bottom of the folded portion 32 of the lead lining I2 by means of bolts 35. The bolts 35 pass through alined holes in the plates 33 and 34, the folded portion 32 of the lead lining and the flanges I3 and I4 to clamp the parts tightly together to form a liquid-tight seal.

A nipple 35 extending through alined holes in the bottom of the outer and inner shells I and I I and the lead lining I2 is welded or otherwise joined to the shells and lining to form liquid-tight seals. The nipple 36 is connected to a discharge pipe 3l through a valve 38, see Fig. 1, so that the mixed material may be drained from the tank. As illustrated in Fig. 3, a thermometer 39 extends through an insulating sleeve 40 inserted through openings in the outer and inner shells I and II and the lead lining I2. Thus, the lead lining l2, constituting the tank proper, is supported by the inner shell II with a large portion of its surface exposed to the conditioning medium in the chamber I by the perforations 30.

An agitator is usually provided for mixing the materials in the tank, being herein illustrated as comprising a pair of paddles 42 and 43 of any suitable form. The paddles 42 and 43 are preferably in the form of blocks having their opposite sides adjacent opposite ends beveled upwardly toward the top to provide inclined faces 46. The paddles 42 and 43 are bolted to the ends of a pair of depending shafts 44 and 45 for rotation thereby and the shafts are of different lengths tol position the paddles at different levels, one above the other. The shafts 44 and 45 are journaled in bearings 4l and 48 at opposite sides of a rotating carrier 4Q to adapt them for bodily movement therewith. The carrier 49, in turn, is supported at the lower end of a shaft 50 journaled in a framework 5I and arranged to be rotated from a pulley 152 through reduction gearing 53. The shafts 44 and 45 have planetary gears 54 at their upper ends in mesh with a sungear 55 xed to the framework 5I to cause the shafts to be rotated on the carrier 4S when the latter is rotated by the shaft 55. Thus, as the paddles are revolved around the interior of the tank their inclined faces 4S agitate the material to cause eddy currents and effect a thorough mixing of the material. A preferred form of mixing tank incorporating the novel features of the present invention having now been described in detail, its mode of operation is next explained.

When sulphonating oils or when mixing chemicals which generate heat the valve 23 is opened to circulate a cooling medium in the outer chamber I5, the drain valve 38 is closed, and the agitating paddles 42 and 43 are set in motion. The oil and acid or other materails are then introduced into the mixing tank I2. As the shaft 55 and carrier 49 connected thereto are rotated from the pulley 52 by means of the reduction gearing 53, the shafts 44 and 45 and paddles 42 and 43 carried thereby are moved bodily through a circular path. The planetary gears 54 meshing with the xed sun-gear 55 during the rotation of the carrier 49 thus cause the shafts 44 and 45 and paddles 42 and 43` connected thereto to be rotated simultaneously with their bodily movement. As the beveled faces 46 on the paddles rotate rapidly in the material they cause it to be agitated and thoroughly mixed and at the same time set up a flow of the material toward the inside surface of the side and bottom walls of the tank or lining I2. As the two chemicals combine, heat is generated at a rapid rate and this is transmitted through the lead tank or lining I2 to the surrounding conditioning medium in the chamber I5. Due to the perforations 34 in the inner shell Il, the conditioning medium directly contacts the outside surface of the lead tank or lining I2 over a considerable portion of its area so that the heat is dissipated as quickly as it generates. It has been determined in practice that a conditioning medium such as water actually seeps and circulates between the outside surface of the lead tank or lining I2 and the portions of the shell Il intermediate the perforations 3Q. It has also been found in actual use that the present mixing tank dissipates the heat generated during the sulphonation'of oils or otherwise at a sufficiently rapid rate to maintain the temperature of the mixture well below its boiling point. After the chemical reaction is completed the valve 38 maybe opened to drain the mixture from the tank I2. If the materials being mixed require heat to complete the chemical reaction the valve 23 is closed and' the valve 22 opened to circulate a heating medium such as hot water or steam through the chamber I5.

Fig. 5 of the drawings illustrates a modied 75 form of construction of the invention wherein the inner shell takes the form of a basket 60 of wiremesh or the like Which is held suspended in the outer shell I in the manner as previously described. The wire-mesh basket 6U, While not as rigid as the inner shell Il illustrated in Figs. 1 to 4, has been found to be capable of properly supporting the lead tank or lining I2, while having the additional advantage of subjecting a greater area of the tank to the conditioning medium through its relatively large interstices.

It will be observed from the foregoing that the present invention provides a mixing tank of novel construction adapted to transfer heat at a rapid rate either from the material being mixed to a conditioning medium, or from the conditioning medium to the materials in the tank. It will also be observed that the invention provides a mixing tank in which the lining may be easily and quickly replaced, and one having a simple construction to adapt it for economical manufacture.

While I have herein described and illustrated two forms of construction of the improved device, it is to be understood that modifications may be made in the structure and arrangement of the parts thereof without departing from the spirit or scopev of the invention. For example, the inner shell may be constructed from an expanded metal sheet to provide perforations therein for directly contacting the surface of the tank or lining with the conditioning medium. Therefore, without limiting myself in this respect, I claim:

1. A jacketed mixing tank comprising an outer imperforate shell, an inner foraminous basket suspended within the outer shell with its bottom and sides spaced from the walls thereof to form a chamber, and a lining Wholly supported on its sides and bottom by the basket and adapted to be directly contacted by a conditioning medium in the chamber.

2. In a device of the type indicated, a mixing tank having a bottom and side walls, and a jacketing chamber surrounding the tank and having a perforated inner shell, said perforated inner shell wholly supporting the tank on its bottom and sides and subjecting the latter to direct contact by a conditioning medium in the chamber admitted through the perforations.

3. In a device of the type indicated, a mixing tank having a bottom and side Walls, a jacket surrounding the tank and having a perforated inner shell for wholly supporting the bottom and sides of the tank and an outer shell spaced from the inner shell to provide a chamber therebetween for the circulation of a conditioning medium.

4. A jacketed mixing tank having anlouter imperforate shell, an inner perforated shell forming a chamber between its Walls and the shell, and a lining having a bottom and sides wholly supported by the perforated shell, said lining being adapted to be directly contacted lby a conditioning medium in the chamber admitted through the perforations in the inner shell.

5. A jacketed mixing tank having an imperforate outer shell, a wire-mesh basket suspended in the outer shell with its bottom and side Walls in spaced relation to the walls thereof to form a chamber therebetween, and a lining wholly supported by the bottom and sides of the wire-mesh basket, said lining being adapted to be directly contacted over its entire area by a conditioning medium in the chamber admitted through the interstices of the wire-mesh basket.

JOHN WILLIAM CORR 

